1. Field of the Invention
The present invention relates to disc drives that drive various discs such as CDs, DVDs, magnetic optical discs, etc., and more specifically relates to a disc drive in which various operation modes can be set by using the moving force between bases.
2. Description of the Related Art
FIGS. 12A and 12B are partly sectioned views showing a disc-clamping unit of a conventional disc drive. In the disc drive shown in FIGS. 12A and 12B, a spindle motor 122 is provided on a drive base 121, and a rotating shaft 123 of the spindle motor 122 projects upward from the drive base 121. In addition, a turntable 124 is fixed to the rotating shaft 123. A clamp base 125, which opposes the drive base 121, is provided with an opening 125a. A clamp 126 is inserted into the opening 125a from the upper side thereof, and a flange 126a formed at the upper end of the clamp 126 is supported by the top surface of the clamp base 125. In addition, the clamp base 125 is also provided with an elastic member 127, which presses the clamp 126 toward the turntable 124.
As shown in FIG. 12A, when the drive base 121 and the clamp base 125 are in a state in which they are further separated from each other, a gap having a size of H0 is provided between the turntable 124 and the clamp 126 for receiving a disc D. When the disc D is inserted into the gap, the clamp base 125 moves downward, and a central opening D1 of the disc D engages with the turntable 124. Accordingly, the disc D is pressed against the turntable 124 by the clamp 126. The disc D is held in this position and is rotated by the spindle motor 122 and the turntable 124.
In the disc drive shown in FIGS. 12A and 12B, various operation modes must be set in association with the operation of moving the clamp base 125 downward and clamping the disc D. For example, positioning members for positioning the disc D must be retracted, and the bases must be released from a locking device, which is provided for locking the bases elastically supported on a chassis. In addition, a head, which is restrained on the chassis, must also be released.
Conventionally, the timing of the above-described operations is controlled by linking mechanical components such as levers, plates, etc., which are provided on the drive base 121 or to the clamp base 125, and by driving such mechanical components by a motor, etc. Thus, a large number of mechanical components are required, and the construction of the disc drive is complex.
In addition, in some disc drives of this type, an up/down switching member, which slides toward the right and the left in FIGS. 12A and 12B, is provided on the drive base 121. The up/down switching member is provided with an inclined groove, which is used for controlling the downward movement of the clamp base 125. It has been suggested that the above-described mechanical components be driven in accordance with the movement of the up/down switching member. However, since the up/down switching member has a large moving range, it is difficult to convert the movement thereof to the movements of other mechanical components provided on the bases.
Accordingly, it is an object of the present invention to provide a disc drive which is free from the above-described problems of the conventional type. More specifically, it is an object of the present invention to provide a disc drive in which various operation modes can be set at the same time the opposing bases approach each other, and in which the mechanism for setting the operation modes is simple.
To this end, according to one embodiment of the present invention, a disc drive comprises a bottom base; a top base which opposes the bottom base with a gap therebetween; a turntable which is provided on one of the bottom base and the top base; a motor for rotating said turntable; a clamp which is provided on the other base, and which presses a disc against the turntable; an up/down switching unit which moves at least one of the bottom base and the top base between a position in proximity to the other base and a position further separated from the other base; a linking member which is rotatably supported by one of the bottom base and the top base at the side thereof, and which is rotated by the other base when the bottom base and the top base move closer to and/or away from each other; and a driving member which is provided on one of the bottom base and the top base, which is operated by the rotational force of the linking member, and which sets an operational mode for driving the disc.
At least one of the bottom base and the top base may be provided with a direction-converting member which converts the rotational force of the linking member to the rotational force along the surfaces of the bases, and wherein the driving member may be moved along the surfaces of the bases due to the operation of the direction-converting member.
The driving member may perform a clamping operation in which the clamp is pressed against the disc. In addition, in the case in which a positioning member for positioning the disc on the turntable is provided, the positioning member may be moved, after the disc is clamped on the turntable, to a position away from the disc.
The driving member may be used for releasing the bases from a locking unit which locks the bases on a chassis, so that the bases are elastically supported on the chassis. In addition, an optical head, etc., which is provided on one of the bases, may be restrained from moving when in a state in which the disc drive is waiting for a disc to be inserted, and the driving member may be used for releasing them when the clamping of the disc is completed.
According to the present invention, the turntable may be provided on the top base, and the clamp may be provided on the bottom base. In addition, both of the top base and the bottom base may be moved toward each other.
Accordingly, in the present invention, various operation modes may be set by utilizing the movement of the bases which approach each other. Thus, each of the operation modes may be set at the same time the clamping of a disc by the bases is completed. In addition, construction for transmitting the power in the mechanism for setting various operation modes may be made simple.